Sharks and rays ‘starved and suffocated’ by plastic debris and ‘ghost’ fishing gear

More than a thousand sharks and rays have become entangled in discarded fishing gear and plastic debris, potentially leading to starvation and suffocation, scientists have warned.

Academics at the University of Exeter feared the issue was going “under the radar” compared to other threats such as over-fishing, and set out to assess the scale of the problem.

Their study has become the first to use Twitter to gather such data, in addition to existing research.

The only reports they got of whale sharks becoming entangled came from social media, compared to none in published studies.

That disparity “emphasises that entanglement is more than likely impacting a significantly greater number of species on a vastly larger scale than this review has presented”, they said.

They are proposing that a “citizen science platform” be set up to help crowdsource reports.

After combining their sources, the researchers found 1,116 reports of the creatures getting caught up.

The majority of entanglements involved abandoned, lost or discarded fishing equipment, known as ghost fishing gear.

Further reports said the creatures had become trapped in plastic packing straps, bags, packaging, elastic cords and clothing.

Species affected included whale sharks, great whites, tiger sharks and basking sharks.

The scientists admit that entanglement is a “far lesser threat” to populations than commercial fishing, but say it is a “major animal welfare concern”, with possible implications for conservation.

They wrote: “Entanglement can lead to starvation, suffocation, immobilisation and ultimately death, making this unequivocally an animal welfare issue, if not of conservation relevance.”

Co-author Professor Brendan Godley, co-ordinator of Exeter University’s marine strategy, said: “Due to the threats of direct over-fishing of sharks and rays and ‘bycatch’ (accidental catching while fishing for other species), the issue of entanglement has perhaps gone a little under the radar.

“We set out to remedy this. Our study was the first to use Twitter to gather such data, and our results from the social media site revealed entanglements of species – and in places – not recorded in the academic papers.”